1. Field of the Invention
The present invention relates generally to safes. More particularly, the present invention relates to an adjustable jamb device for securing door bolts in an open jamb-type safe.
2. Related Art
High security metal safes typically have a heavy steel door that, when closed, is secured by a series of hardened steel bolts that extend from the door into the frame of the safe surrounding the door. A recess or pocket is provided in the door frame for each of the door bolts. The door bolts are aligned with the pockets, and slide thereinto when the safe is locked. While these types of safes are very secure, they tend to be very expensive and very heavy, and are not generally suitable for a typical consumer.
Most consumers with the need for a safe are more likely to purchase a lower cost open-jamb type safe. These safes are typically fabricated of thinner steel than high security safes (i.e. sheet steel, rather than steel plates), and are intended to provide moderate security with high fire protection. The interior of the safe may include gun racks, shelves, file drawers, and other storage systems for holding various types of valuables such as cash, coins, jewels, stocks, bonds, important documents, records, electronic storage media (e.g. videotapes, floppy disks, compact disks, etc.) guns, and so forth. Gun safes of this type have become particularly popular in recent years, particularly in view of some widely publicized incidents related to unsecure storage of firearms.
Like their high security counterparts, lower cost open jamb-type safes comprise a steel case with a door that is secured closed by a series of hardened steel door bolts. However, unlike a high security safe, an open-jamb type safe simply has an inside door jamb against which all the bolts press, rather than having individual sleeves or pockets into which each bolt slides. When the bolts are extended, the door cannot open because the bolts press against the inside of the door frame.
Unfortunately, with this type of locking mechanism, open jamb-type safes present some common problems. One problem is that when the door is closed and bolted, there tends to be some flexure of the door relative to the door frame. One can actually pull on a bolted door and watch the edge of the door move outward next to the frame. This condition does not necessarily represent a functional flaw of the safe, but it is objectionable to consumers, and gives the impression of low quality goods.
This condition has several causes. Because they are not intended as high-priced, high security safes, manufacturing tolerances for low cost open jamb-type safes are generally lower than for high security safes. Consequently, the alignment of the door locking bolts may vary slightly, such that when the bolts are extended, they may not uniformly contact the inside of the door jamb. This problem is compounded by the presence of a resilient door seal strip, which allows some uniform give between the door and the door frame. To provide better and more uniform bearing, several approaches have been attempted. Some manufacturers provide a flexible steel flange along the length of the door jamb. When the bolts extend, they deflect the flange, thus providing more positive bearing for the bolts, regardless of any slight misalignment. However, a common flange for a number of bolts does not necessarily solve the problem of non-uniform bearing, because one single flange contacts all bolts, regardless of their actual alignment. Thus, the position of one bolt may deflect the flange away from contact with an adjacent bolt. Additionally, because the flange is flexible, the door flex problem remains.
Furthermore, the presence of a relatively large steel part (the common door flange) within a safe and directly connected to an inner portion of the safe cabinet presents fire resistance problems. Since metals are thermal conductors, it is important to limit the amount of exposed metal within a safe in order to promote fire and heat resistant properties. A large metal flange inside the safe will tend to aggravate this situation.
Another approach to the problem is to provide an individual flexible flange corresponding to each bolt. These can be individually bent to the correct position for contact with each bolt. While this approach addresses the misalignment problem, it does not prevent door flexure because each flange is flexible. Pulling on the door simply deflects all flanges.